emulator: ClownMDEmu
type: standalone + libretro
core_classification: official_port
source: "https://github.com/Clownacy/clownmdemu-libretro"
upstream: "https://github.com/Clownacy/clownmdemu"
profiled_date: "2026-03-23"
core_version: "Git"
display_name: "Sega - MD/CD (ClownMDEmu)"
cores:
  - clownmdemu
systems:
  - sega-megadrive
  - sega-megacd

notes: |
  Mega Drive/Genesis and Mega CD emulator by Clownacy. Supports cartridge
  (bin/md/gen) and CD (cue/iso/chd) formats, plus a subsystem for
  cartridge+CD combo (Mega CD Mode 1). Mega CD boot ROM is an open-source
  replacement compiled into the binary (mega-cd-boot-rom.c, 32 KB). Sub-CPU
  BIOS calls handled via HLE. TMSS not implemented. No external files needed.

files: []

analysis:
  tmss:
    supported: false

  megacd_bios:
    external_required: false
    builtin_boot_rom: true
    boot_rom_source: "https://github.com/Clownacy/clownmdemu-mcd-boot"
    boot_rom_location: "source/mega-cd-boot-rom.c (16384 uint16 entries = 32 KB)"
    bus_mapping: "0x400000-0x41FFFF (address & 0x20000 == 0)"
    source_ref: "bus-main-m68k.c:19-21, bus-main-m68k.c:501-513"
    bios_hle: true
    hle_source_ref: "bus-sub-m68k.c:64 (MegaCDBIOSCall)"